I came across this "Special" case. It seems that Firebird enforces
not null in the primary key when you create the table. (Makes 100%
sense) But sadly, it doesn't enforce the user from altering the
field. I was able to do an ALTER Table and remove the not null from a
primary composite key.

Never the less, this causes havoc on a few tool, IB Experts and IBO
Objects both goes nuts when they see a NULL in the primary key. IB
Experts doesn't apply the a change on existing records, and IBO can't
sync. Either way, this is a problem with them.

If I update the field manually (UPDATE SQL) it works. So, I don't
think there is a "Bug" in firebird, at least none that I've seen yet.

My question is, shouldn't the primary key not null requirement be
enforced ALSO when you do an alter? I don't think it makes any sense
to allow nulls in a key.

Oracle does enforces this when you do an alter. It generates polite
message on your ignorance. :)

I'm using firebird 1.5.

Thanks,

Have a nice day.